The present invention relates to a method of optical signal transportation within an integrated circuit (IC), an electronic device, etc. More particularly, it provides a light transmission system for an electronic device in which a signal is transmitted to a desired layer even when layers having different functions are accumulated and integrated as in a three-dimensional integrated circuit.
In the operation of an electronic device, internal information signals have important roles. Especially in the electronic device of a structure wherein parts of different functions are connected and integrated in parallel or in layers, the mutual transfer of information is indispensable. To this end, a method of electrically connecting both the parts is adopted most commonly. This is described in `Japan Journal of Applied Physics`, Vol. 20, No. 9 (1981), pp. L623-L626.
However, in such a case where the functional parts are arranged separately with an insulator therebetween or where they form a multilayer structure vertically, an electrical interconnection has been impossible or a complicated process has been required.